If you are using the Wix in Visual Studio (known as 'Votive') and need to set one or more preprocessor variables, it is rather simple. If you right-click on the Wix project, select 'Properties', then the 'Build' tab, you simply populate the 'Define preprocessor variables:' text box like so:
Name1=Value1;Name2=Value2If you are using MSBuild, or editing the .wixproj file itself, this translates to the contents of the 'DefineConstants' element, which is where Votive stores what you put in that text box.
Things, however, are not really clear (or documented) if you need to set Name1 in the example above equal to a semicolon delimited list - for example "one;two;three" - so lets try it this way:
Name1=one;two;three;Name2=Value2Candle.exe is passed (which is obviously incorrect based on our intentions):
-dName1=one -dtwo -dthree -dName2=Value2The solution is NOT to put quotes around the list (my first guess), but to replace the semicolons that break up the list (and only the ones in the list) with '%3b', like so:
-dName1=one;two;three -dName2=Value2I do not know if this is way you would handle this situation in anything newer than Wix 3.0 - I haven't updated to 3.5 yet.